1. Field of the Invention
The present invention is directed to an x-ray computed tomography apparatus of the type having an annular x-ray source surrounding a measuring field, the annular x-ray source having an annular anode that is scanned by an electron beam for generating a rotating x-ray beam. The geometry of such an x-ray computed tomography apparatus shall be referred to below as EBT (electron beam tomography) geometry.
2. Description of the Prior Art
An especially fast scanning of an examination subject is possible with an x-ray computed tomography apparatus of the above type, so that motion unsharpness is largely suppressed. In order for the x-ray beam to enter unimpeded into the measuring field wherein the examination subject lies, the radiation detector that is likewise annularly fashioned and is composed of a row of detector elements arranged laterally next to the exit window of the x-ray beam. This permits that the x-ray beam to emerge unimpeded from this window and to be incident on the x-ray detector after leaving the measuring field. To this end, the x-ray beam is inclined at an angle relative to its rotational axis that deviates slightly from 90.degree..